Our invention relates to processing systems and more particularly to parallel processing systems using data shuffling arrangements. In large scale communication systems, switching functions adapted to accommodate wide band information require complex sorting operations in order to interconnect large numbers of subscribers. Similarly, many data processing systems need complex arrangements to perform functions such as fast Fourier transforms, polynomial evaluation, data sorting, and matrix manipulation. Many of these data processing operations may be accomplished by shuffling data elements in accordance with well-known algorithms.
The article, "Parallel Processing with the Perfect Shuffle," by Harold S. Stone appearing in the IEEE Transactions on Computers, February 1971, pp. 153-161, describes the application of the well-known perfect shuffle technique to such data processing and switching problems. U.S. Pat. No. 4,161,036 issued to S. Brent Morris et al, July 10, 1979, discloses random and sequential accessing techniques in dynamic memories utilizing shuffling operations. The perfect shuttle technique is well adapted to perform many switching and data processing functions, and high density logic circuits are available for its implementation. The complex interconnections required for electrical implementation of the shuffling process, however, are difficult to achieve using prior art arrangements. The article, "Optical Interconnections for VLSI Systems," by Joseph W. Goodman et al appearing in Proceedings of the IEEE, Vol. 72, No. 7, July 1984, pp. 850-866, discloses various optical interconnections between density integrated circuit chips which permit electrical circuit elements to perform large scale parallel processing involving rearrangement of information elements such as the perfect shuffle.
Optical systems performing data processing functions are well known in the art. U.S. Pat. No. 3,872,293, issued Mar. 18, 1975 to Eugene L. Green, discloses a multi-dimensional Fourier transform optical processor. U.S. Pat. No. 3,944,820, issued to Larry B. Stotts, Mar. 16, 1976, discloses a high speed optical matrix multiplier system using analog processing techniques. U.S. Pat. No. 4,187,000, issued Feb. 5, 1980 to James W. Constant, describes an analog addressable optical computer and filter arrangement. These patents rely on analog computation and are not applicable to processing of information based on perfect shuffle principles. U.S. Pat. No. 4,418,394, issued to Anthony M. Tai on Nov. 29, 1983, discloses an optical residue arithmetic computer having a programmable computation module in which optical paths are determined by electrical fields. It is an object of the invention to provide an improved optical shuffling arrangement adapted to perform optical parallel processing of digital information.